Voice of the DBA

Author: way0utwest

  • A Full Backup can Impact a Log Backup–MCM Prep

    In the early days of SQL Server you could not run a log backup while a full backup was running. In fact,you tried to schedule them apart from each other early in my career to prevent collisions. Nothing bad happens, but it does cause failures in your monitoring and those are annoying.

    In modern versions of SQL Server, you can run log backups and simultaneous full backups. They don’t collide or block each other, but there is a way that the full backup impacts a log backup.

    If you start a full backup, once all data pages are written to the backup device, the log records that were created since the start of the full backup are added to the full backup file. This allows the redo/undo process to complete and this gives you a full backup set that is intact as of the point in time in which the data pages finish writing.

    If you run a log backup, typically the log records are written out, and then the VLFs in the log file that were written to disk are marked as inactive.

    However since those log records are needed for the full backup to be complete, the log backup cannot clear those VLFs when the log backup finishes. That process still occurs, and technically this is part of the log backup, but it is deferred until the full backup completes.

  • Hybrid Hires

    I'd like to see more of these in the US

    There was a lot of talk about various hybrid technologies at the recent Detroit Auto Show, with many new models being displayed that use some type of hybrid technology. There are plenty of people that don’t love the technology, but my Prius has performed well for me over the last three and a half years I’ve had it. Who knows, I might even buy another one.

    The past two or three years have been a down economy around the world. As I’ve traveled to meet many SQL Server professionals at events all around the US, I’ve found that many of them have struggled with having more work and less resources to get it done. There are also many people who have lost their jobs or had trouble finding a job. Quite a few others have a hard time trying to get work done while worrying about their own job security. The downturn has not been pervasive, however, and there are plenty of technical professionals for whom the last two years have been business as usual as they go to work every day.

    At some point most of us will need to look for another job, and when we do, I think those of us that are well rounded DBAs will be in a good position. Data professionals often understand technology, and the business impact of data. There was some data on recent good trends in IT hiring summarized in this article that talks about job growth. In the article it mentions how there are lots of potential IT related positions where people are being hired to analyze data and statistics, as business/IT hybrids.

    I’m not sure that the idea of being a hybrid worker appeals to me, but I can see where technical and business skills are valuable for a data professional. You want to use these skills to market yourself and bring attention to your resume. It’s why a good IT worker will learn about the business of their employer and how it works.

    When you’re looking for a job, showing off your business skills alongside your technical skills can give you more opportunities to choose from and hopefully help you find the job that fits you best.

    Steve Jones

    (originally published at http://www.sqlservercentral.com/articles/Editorial/72344/)

    The Voice of the DBA Podcasts

  • Work Isn’t the Most Important Thing

    brokenpipe_cI had quite an adventure today, away from work. We had a pipe freeze in the house, a sick kid, and then a plumber call when the pipe broke. All in all, with school closed and kids home, I haven’t gotten much work done. My wife ended up also missing a bunch of work at a busy time. I leave for Cleveland Friday morning, so it’s already a short week and that adds to the stress.

    But that happens. Life gets in the way of work, and there are times you need to let things go. I know there are friends that have gotten off of work this week because of the weather, and I’ve had companies close. When I lived in Virginia, we closed the office sometimes with hurricanes or strong storms, helping employees to manage their lives outside of work. I’ve helped hang plywood and even get boats out of the water in preparation for the storm.

    I think that a part of what business has to include is social responsibility. It can come with benefits like goodwill that come from donating back to schools, but I think that the highest level of profit you can make is not the way business should be run. You should consider what helps your employees, what helps your community, and what is the best way to integrate your company into the world outside of your profit.

    Hopefully your employer understands that.

  • What’s a Passive Server?

    Licensing software is often a more complicated process than I think it should be. Licensing database software seems to be even more difficult to understand, especially when you start to talk about the various high availability (HA) scenarios, virtualized  servers, separate machines to process SSIS packages and who knows what other configurations, not to mention the licensing changes with each new version of SQL Server.

    I was following a licensing debate  about how you license passive servers in an HA situation. I have always understood from the SQL Server licensing documents that if you have a passive server, it does not require a license for the SQL Server software. However it’s not that simple, or at least, it doesn’t appear that way to me.

    Suppose you have an primary instance that mirrors its database to another server. The mirror instance doesn’t need a license for that database, but what about if you also log ship your primary database to a third server? Does the third server need a license if it’s also “passive”? I assume that if you had second database on the mirror instance being used for another application, you’d need a license for that instance, but what if you only have a “DBA database” that gathers performance monitoring information for that mirror database? Is that “passive”?

    Suppose I have a 6 node cluster, and I have 4 active nodes and two passive ones, do I still have 2 other “passive” licenses for log shipped servers? Or can I log ship to 4 separate servers? That doesn’t even bring this clause into play:  “The passive server can take the duties of the active server for 30 days. Afterwards, it must be licensed accordingly” (from 2005 licensing). It almost feels like I am studying some type of Microsoft Internal Licensing Framework in preparation for some type of certification.

    To me, the simple way to handle this is to say that passive servers, those not doing any work for the business that owns them, don’t require a license. The exception would be for internal monitoring or maintenance on the passive server (backup restores, DBCC checks, DBA sysadmin monitoring). I doubt we’ll get something that simple, but that’s what I think would be fair.

    Steve Jones

    (originally published at http://www.sqlservercentral.com/articles/Editorial/72338/)

    The Voice of the DBA Podcasts